1. Field of the Invention
The present invention relates to a plant operation system that controls and monitors various kinds of plant apparatuses such as a nuclear plant and a power generation plant, and particularly to a plant operation system provided with a normal plant operation control system and a backup plant operation control system.
2. Description of the Related Art
Among conventional plant monitoring control systems, there exists a plant monitoring control system provided with a means that selectively displays a controlling status (a controlling state, a waiting state, a holding state, and the like) of a controller and the kind of a control subject (temperature control, pressure control, and the like) on a guidance display device in an operation apparatus so as to accurately comprehend the controlling status and the kind of a control subject (refer to Japanese Patent Application Laid-Open No. 2000-89819 (FIGS. 2, 4, and 8)).
Additionally, among conventional plant monitoring control systems, there exists a plant monitoring control system in which a common image is displayed on respective display screens formed on the front surface and the rear surface of a display device, by means of internal processing circuits for the display screens; and even in the case where the internal processing circuit for one of the display screens fails, monitoring of the same image and signal-input operation can continuously be performed by use of the other display screen; thus, mutual backup between the front and rear display screens can be performed (refer to Japanese Patent Application Laid-Open No. 2001-117632).
Additionally, among plant monitoring control systems, there exists an operation support system in which there are provided a transmission unit for performing communication with a teleconference system located in the vicinity of the apparatuses to be operated; a transmission unit for performing, through a communication network, communication with higher-hierarchy computers installed in a sales office, a control site, a backup control site, and the like; and a processing unit that implements data processing by means of a CPU (refer to Japanese Patent Application Laid-Open No. 2008-123118 (FIG. 8)).
In a conventional plant monitoring control system, there exists a backup plant operation control system configured for performing the backup for individual apparatuses and for displaying selectively; however, it is hardly considered to prepare a backup plant operation control system for a failure of a plant operation control system.
With regard to a plant operation system, it is important that a backup plant operation control system is provided in order to continue the operation of a plant in the case where a failure of a plant operation control system occurs during the operation of the plant.
In the case where, as described above, a backup plant operation control system is provided and a failure occurs in a plant operation control system during the operation of a plant, and then the plant operation control system is replaced by the backup plant operation control system, a position (activate/stop, open/close, or the like), of the operation device of a plant apparatus, which was ineffective when the normal plant operation control system was in an operation state may be effective in the backup plant operation control system. As described above, there has been a problem that, in the case where the plant operation control systems are changed, a position, of the operation device, which differs from the position when normal plant operation is performed becomes effective, a problem is posed while the plant is operated, for example, the output of the plant decreases.